2015/07/07 by P.-E. Tremblay, P. -E. Tremblay, A. Gianninas +6 · 86 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Atmosphere (unit) #Binary number #Convection #Effective temperature #Pulsar #Pulsars and Gravitational Waves Research #RADIUS #Spectral line #Stellar atmosphere #Stellar, planetary, and galactic studies #White dwarf #astro-ph.SR
paper · pdf · doi:10.1088/0004-637x/809/2/148
published in The Astrophysical Journal 809(2), 148 (IOP Publishing) · 11 pages, 8 figures, accepted for publication in the Astrophysical Journal
arxiv created 2015/07/07 · openalex publication_date 2015/08/19 · arxiv updated 2015/08/26 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present an extended grid of mean three-dimensional (3D) spectra for low-mass, pure-hydrogen atmosphere DA white dwarfs (WDs). We use CO5BOLD radiation-hydrodynamics 3D simulations covering T eff = 6000–11,500 K and log g = 5–6.5 ( g in cm s −2 ) to derive analytical functions to convert spectroscopically determined 1D temperatures and surface gravities to 3D atmospheric parameters. Along with the previously published 3D models, the 1D to 3D corrections are now available for essentially all known convective DA WDs (i.e., log g = 5–9). For low-mass WDs, the correction in temperature is relatively small (a few percent at the most), but the surface gravities measured from the 3D models are lower by as much as 0.35 dex. We revisit the spectroscopic analysis of the extremely low-mass (ELM) WDs, and demonstrate that the 3D models largely resolve the discrepancies seen in the radius and mass measurements for relatively cool ELM WDs in eclipsing double WD and WD + millisecond pulsar binary systems. We also use the 3D corrections to revise the boundaries of the ZZ Ceti instability strip, including the recently found ELM pulsators.